Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Mater Sci Eng C Mater Biol Appl ; 118: 111341, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33254968

RESUMEN

BACKGROUND: Although silver nanoparticles (SNP) have proven antimicrobial activity against different types of microorganisms, the effect of SNP incorporation into acrylic resin to control Candida albicans biofilm formation aiming at the prevention of Candida-associated denture stomatitis has not yet been fully elucidated. OBJECTIVES: This study aimed to evaluate the antimicrobial effect of an acrylic resin containing SNP on C. albicans biofilm growth, the flexural strength of this material and tissue reaction in the subcutaneous connective tissue of rats to SNP. METHOD: SNP were synthesized through silver nitrate reduction by sodium citrate. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to verify the size and colloidal stability. SNP were added to acrylic resin monomer (Lucitone 550) at 0.05, 0.5 and 5 vol%. The antimicrobial effect against C. albicans (ATCC 10231) was investigated by the enumeration of colony-forming units (CFUs) and SEM. The three-point bending test was performed to analyze the flexural strength. Tissue reaction was evaluated after 7 and 60 days of implantation in the connective tissue of Wistar rats. RESULTS: Spherical particles of 5 and 10 nm were obtained. SNP at 0.05 and 0.5% incorporated into acrylic resin was effective in reducing C. albicans biofilm growth (p < .001). SEM revealed that the material was able to disrupt C. albicans biofilm formation and did not reduce the flexural strength compared to control (p > .05). The inflammatory response observed 60 days after implantation SNP in the subcutaneous tissue was similar to control. CONCLUSION: It was concluded that SNP addition at 0.05 and 0.5% into acrylic resin exhibited antimicrobial effects against C. albicans biofilm, did not interfere in the flexural strength and may be considered biocompatible.

2.
Arch Oral Biol ; 111: 104643, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31918345

RESUMEN

AIM: To evaluate the cytotoxicity and inflammatory response of different types of provisional restorative materials to mice gingival fibroblasts. METHODS: Cytotoxicity of provisional material discs (thermal-polymerized acrylic resin; auto-polymerized acrylic resin; bisacrylic resin; nano-ceramic resin for CAD/CAM and prefabricated polymer block for CAD/CAM) to Mice (Balb/c) gingival cell were investigated under direct and indirect contact (extracts) at 24, 48 and 72 h, using the MTT and Alamar blue assays. Materials extracts (24 h) were applied to the cell culture (indirect contact) or cells were seeded on discs of provisional materials, and the cytotoxicity and production of IL-6, IL-1ß and TNF-α after 24, 48 and 72 h were analyzed through MTT, Alamar Blue® and ELISA. Culture medium was used as control for indirect contact assay (extract) and the surfaces of the wells without discs of provisional materials were used as control for direct contact assay. Results were analysed statistically by ANOVA followed by the Bonferroni-Test correction. Statistically significant differences were considered if P was < .05. RESULTS: Auto-polymerized and bisacrylic resins (direct contact) reduced cell viability after 24, 48 and 72 h compared to control (P < .05). Indirect contact (extract) was not cytotoxic to cells at all periods compared to control (P > .05). Auto-polymerized and bisacrylic resins increased IL-6, IL-1ß and TNF-α levels mainly at 24 h when compared to the other materials (P < .001). CONCLUSION: Auto-polymerized and bisacrylic were more cytotoxic to mice gingival fibroblasts. CAD/CAM nano ceramic resin and prefabricated polymer blocks are more predictable materials to preserve the periodontal soft tissues.


Asunto(s)
Resinas Acrílicas , Materiales Dentales , Animales , Cerámica , Resinas Compuestas , Diseño Asistido por Computadora , Ensayo de Materiales , Ratones , Propiedades de Superficie
3.
J Endod ; 42(6): 953-60, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27118468

RESUMEN

INTRODUCTION: Silver nanoparticles have been used for different purposes in dentistry, including endodontic treatments. The aim of this study was to determine the cytotoxicity of different types of silver nanoparticles on mouse fibroblast cell line L929 and the reaction of subcutaneous connective tissue of Wistar rats to these nanoparticles. METHODS: Silver nanoparticles of an average size of 5 nm were synthesized with ammonia (SNA) or polyvinylpyrrolidone (SNP). L929 was exposed to SNA and SNP (0.1-100 µg/mL), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and enzyme-linked immunosorbent assays were performed after 6, 24, and 48 hours. Culture medium was used as the control. Sixteen rats received, individually, 3 polyethylene tubes filled with a fibrin sponge embedded in 100 µL SNA or SNP (1 µg/mL). A fibrin sponge with no embedding was the control. Tissue reaction was performed qualitatively and quantitatively after 7, 15, 30, and 90 days of implantation in the dorsal connective tissue of Wistar rats. RESULTS: SNA and SNP were cytotoxic to L929 in higher concentrations, with SNA significantly more toxic than SNP. SNA and SNP did not induce significant interleukin-1ß and interleukin-6 production. The release of stem cell factor by L929 increased 48 hours after the treatment with SNP at 5 µg/mL. Histologic examination showed that the inflammatory responses caused by SNA and SNP at 1 µg/mL were similar to the control in all experimental periods. CONCLUSIONS: It was concluded that SNA and SNP were not cytotoxic at 25 µg/mL or lower concentrations. However, for safe clinical use, further studies establishing others points of its toxicologic profile are recommended.


Asunto(s)
Ensayo de Materiales/métodos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Plata/química , Plata/toxicidad , Pruebas de Toxicidad/métodos , Amoníaco/química , Animales , Línea Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Tejido Conectivo/efectos de los fármacos , Materiales Dentales/química , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Fibrina/química , Fibroblastos/efectos de los fármacos , Inflamación , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Nanopartículas del Metal/administración & dosificación , Ratones , Microscopía Electrónica de Transmisión , Neutrófilos/efectos de los fármacos , Neutrófilos/patología , Tamaño de la Partícula , Poríferos , Povidona/química , Ratas , Ratas Wistar , Plata/administración & dosificación , Factor de Células Madre/efectos de los fármacos , Tejido Subcutáneo/efectos de los fármacos , Sales de Tetrazolio , Tiazoles , Factores de Tiempo
4.
J Prosthet Dent ; 115(3): 259-62, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26581660

RESUMEN

A 65-year-old woman presented with an ulcerated lesion in the alveolar ridge mucosa, which appeared after new dentures had been inserted. Despite many treatment attempts, the lesion did not recede, even with the interruption of denture wearing. A biopsy was performed, and histopathologic examination revealed an ulcerated, invasive, poorly differentiated oral squamous cell carcinoma. The time from the patient's first contact with the prosthodontist because of the lesion until the appropriate diagnosis was established was approximately 6 months. This clinical report documents a significant delay in the oral squamous cell carcinoma diagnosis and treatment because of a clinical misdiagnosis of a traumatic ulcer resulting from complete dentures. Prosthodontists should be aware of the importance of early diagnosis of oral cancer among elderly prosthesis wearers.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Neoplasias de la Boca/diagnóstico , Úlcera/diagnóstico , Anciano , Dentadura Completa/efectos adversos , Diagnóstico Diferencial , Femenino , Humanos , Estomatitis Subprotética , Úlcera/complicaciones
5.
J Prosthodont Res ; 59(1): 42-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25168655

RESUMEN

PURPOSE: The aim of this study was to investigate the susceptibility of Candida albicans and Candida glabrata biofilm development, in their intermediate and maturation stages, to the influence of silver nanoparticles (SN). METHODS: SN (5 nm) suspensions were synthesized via reduction of silver nitrate by a solution of sodium citrate. These suspensions were used to treat Candida biofilms for five hours, grown on acrylic surfaces for 24-h (intermediate stage) and 48-h (maturation stage), and their efficacy was determined by total biomass (using crystal violet staining) and colony forming units (CFUs) quantification. RESULTS: SN promoted significant reductions (p<0.05) in the total biomass and number of CFUs of Candida biofilms, ranging from 23% to 51.5% and 0.63 to 1.59-log10, respectively. Moreover, there were no significant differences in the total biofilm biomass (p>0.05), when the different stages of biofilm development (24 or 48h) were exposed to SN. Comparing the number of CFUs between 24- and 48-h biofilms treated with SN, a significant difference (p<0.05) was found only for the C. albicans 324LA/94 strain. CONCLUSIONS: In general, the intermediate and maturation stages of biofilm development do not interfere in the susceptibility of C. albicans and C. glabrata biofilms to SN. These findings are fundamental for the deployment of new therapies aimed at preventing denture stomatitis.


Asunto(s)
Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Candida glabrata/efectos de los fármacos , Candida glabrata/fisiología , Nanopartículas del Metal , Compuestos de Plata/farmacología , Candida albicans/citología , Candida albicans/crecimiento & desarrollo , Candida glabrata/citología , Candida glabrata/crecimiento & desarrollo , Farmacorresistencia Fúngica , Compuestos de Plata/síntesis química
6.
Med Mycol ; 52(6): 627-35, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24951722

RESUMEN

Our aim in this study was to evaluate how the chemical stability of silver nanoparticles (SNs) influences their efficacy against Candida albicans and C. glabrata biofilms. Several parameters of SN stability were tested, namely, temperature (50ºC, 70ºC, and 100ºC), pH (5.0 and 9.0), and time of contact (5 h and 24 h) with biofilms. The control was defined as SNs without temperature treatment, pH 7, and 24 h of contact. These colloidal suspensions at 54 mg/L were used to treat mature Candida biofilms (48 h) formed on acrylic. Their efficacy was determined by total biomass and colony-forming unit quantification. Data were analyzed using analysis of variance and the Bonferroni post hoc test (α = 0.05). The temperature and pH variations of SNs did not affect their efficacy against the viable cells of Candida biofilms (P > 0.05). Moreover, the treatment periods were not decisive in terms of the susceptibility of Candida biofilms to SNs. These findings provide an important advantage of SNs that may be useful in the treatment of Candida-associated denture stomatitis.


Asunto(s)
Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Dentaduras/microbiología , Nanopartículas , Plata/farmacología , Acrilatos , Biomasa , Candida albicans/fisiología , Candida glabrata/fisiología , Recuento de Colonia Microbiana , Humanos , Concentración de Iones de Hidrógeno , Temperatura , Factores de Tiempo
7.
Artículo en Inglés | MEDLINE | ID: mdl-23733082

RESUMEN

BACKGROUND: Although the long-term success of implant treatment has been well- established, failures can still occur and the smoking habit has been reported as a risk factor for implant loss. A literature review on the effects of smoking on the survival of dental implants was undertaken. METHODS AND RESULTS: Medline database was used to carry out the review with the keywords "osseointegration", "smoking" and "bone healing". The cigarette has more than 4,000 bioactive chemical components with potential toxic effects to human tissues including bone. Nicotine is the main component of the cigarette and it is frequently associated with bone healing failures. Since smoking negatively affects the osseointegration of dental implants, the main target is to quit the consumption of cigarettes. CONCLUSION: Nevertheless, the smoking habit should not be an absolute contraindication for implant treatment, but, patients should be advised that they are at a greater risk of implant failure.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales/efectos adversos , Fracaso de la Restauración Dental/estadística & datos numéricos , Nicotina/efectos adversos , Fumar/efectos adversos , Implantación Dental Endoósea/efectos adversos , Humanos , Factores de Riesgo
8.
J Prosthodont Res ; 57(1): 36-41, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23146331

RESUMEN

PURPOSE: The aim of this study was to evaluate the impact of treatment with new complete dentures on oral health-related quality of life and satisfaction of edentulous patients attending the Prosthodontic Department in a Dental School in Brazil. METHODS: A total of 70 edentulous subjects (37-86 years) treated by undergradute students at the Araçatuba Dental School, University of State of São Paulo, were accessed. A specific questionnaire for edentulous patients (EDENT) based on the Oral Health Impact Profile (OHIP-EDENT) was applied to collect information on patient oral health-related quality of life. Questions related to the personal satisfaction of the edentulous patients with their complete dentures were also included. The patients were accessed before the treatment, and 3 months after receiving the new dentures. RESULTS: After rehabilitation with new complete dentures, all domains of OHIP-EDENT showed significant improvements. There was also a significant improvement in patient satisfaction after placement of new complete dentures. Furthermore, it was possible to observe association between upper denture satisfaction and age. CONCLUSION: Conventional complete dentures may have a positive impact on oral health-related quality of life and satisfaction of edentulous patients.


Asunto(s)
Dentadura Completa/psicología , Salud Bucal , Satisfacción Personal , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Boca Edéntula/psicología , Boca Edéntula/terapia
9.
Araçatuba; s.n; 2013. 108 p. ilus, graf, tab.
Tesis en Inglés | LILACS, BBO - Odontología | ID: biblio-866915

RESUMEN

O objetivo deste estudo foi investigar o efeito de diferentes soluções coloidais de nanopartículas de prata sobre a viabilidade celular de fibroblastos (linhagem L929) e sobre a resposta inflamatória de tecido subcutâneo de ratos. Nanopartículas de prata (SNP) com tamanho médio de 5 nm foram sintetizadas através da redução do nitrato de prata pelo citrato de sódio e estabilizadas com amônia (SNP-A) ou polivinilpirrolidona (SNP-P). Para avaliar a viabilidade celular, células L929 foram expostas SNP e agentes estabilizantes (amônia (NH3) e polivinilpirrolidona (PVP)) (0,1 – 100 μg/mL), e após 6, 24 e 48 h foi realizado o ensaio de citotoxicidade celular pelo método do MTT. A resposta tecidual foi realizada com tubos de polietileno contendo SNP (1.0 μg/mL; 540 μg/mL) e agentes estabilizantes (NH3 0.13 x 10-3 mol/L e PVP 0.19 g/L) implantados no tecido conjuntivo dorsal de ratos Wistar por 7, 15, 30, 60 e 90 dias. Os espécimes foram corados com hematoxilina e eosina e foram realizadas avaliações qualitativa e quantitativa. SNP inibiram a viabilidade celular no teste in vitro de maneira concentração-dependente. SNP-A foram mais tóxicas para L929 que as partículas estabilizadas com PVP. O exame histológico mostrou que SNP 540 μg/mL induziram reação tecidual significantemente mais intensa em 30 e 60 dias comparado aos grupos controles (solução fisiológica 0,9% e fibrina) nos mesmos períodos. As respostas inflamatórias causadas por SNP 1,0 μg/mL, NH3 0,13 x 10- 3 mol/L e PVP 0,19 g/L foram similares aos controles em todos os períodos experimentais. Foi possível concluir que a exposição à SNP reduziu a viabilidade de células L929 de maneira concentração-dependente. O tipo de agente estabilizante interferiu na citotoxicidade sendo SNP-A mais tóxica para L929. Ambos os tipos de soluções coloidais de nanopartículas de prata (SNP-A e SNP-P) a 540 µg/mL induziram significante resposta inflamatória no tecido subcutâneo de rato


The aim of this study was to investigate the effect of different colloidal silver nanoparticles on cell viability of mouse fibroblasts (cell line L929) and on the subcutaneous connective tissue reaction of rats. Silver nanoparticles (SNP) of average size 5 nm were synthesized by the reduction of silver nitrate through sodium citrate and were stabilized with ammonia (SNP-A) or polyvinylpyrrolidone (SNP-P). To evaluate the cell viability, L929 cell were exposure to silver nanoparticles (0.1-100 μg/mL), and after 6, 24 and 48h MTT assay was performed. The tissue reaction was carried out with polyethylene tubes containing silver nanoparticles (1.0 μg/mL; 540 μg/mL) implanted in the dorsal connective tissue of Wistar rats for 7, 15, 30, 60, and 90 days. The specimens were stained with hematoxylin and eosin and qualitative and quantitative evaluations of the reaction were carried out. Silver nanoparticles inhibited the cell viability in the in vitro test in a concentration-dependent manner. SNP-A were more toxic to L929 than particles stabilized with polyvinylpyrrolidone (PVP). Histological examination showed that SNP at 540 μg/mL induced significant tissue reaction on 30 and 60 days after implantation compared to the controls groups (fibrin and saline 0.9%) at the same periods. The inflammatory responses caused by SNP at 1.0 μg/ml, NH3 at 0.13 x 10-3 mol/L and PVP at 0.19 g/L solutions were similar to the controls groups in all experimental periods. It was possible to conclude that SNP exposure decreased the viability of L929 cells in a concentration-dependent manner. The type of stabilizing agent interfered on the cytotoxicity of SNP being SNP-A more toxic to L929. Also, both colloidal silver nanoparticles (SNP-A and SNP-P) at 540 μg/mL induced significant inflammatory response in rat’s subcutaneous tissue


Asunto(s)
Ensayo de Materiales , Nanopartículas del Metal , Plata , Toxicidad
10.
Araçatuba; s.n; 2013. 108 p. ilus, graf, tab.
Tesis en Inglés | LILACS, BBO - Odontología | ID: biblio-870121

RESUMEN

O objetivo deste estudo foi investigar o efeito de diferentes soluções coloidais de nanopartículas de prata sobre a viabilidade celular de fibroblastos (linhagem L929) e sobre a resposta inflamatória de tecido subcutâneo de ratos. Nanopartículas de prata (SNP) com tamanho médio de 5 nm foram sintetizadas através da redução do nitrato de prata pelo citrato de sódio e estabilizadas com amônia (SNP-A) ou polivinilpirrolidona (SNP-P). Para avaliar a viabilidade celular, células L929 foram expostas SNP e agentes estabilizantes (amônia (NH3) e polivinilpirrolidona (PVP)) (0,1 – 100 μg/mL), e após 6, 24 e 48 h foi realizado o ensaio de citotoxicidade celular pelo método do MTT. A resposta tecidual foi realizada com tubos de polietileno contendo SNP (1.0 μg/mL; 540 μg/mL) e agentes estabilizantes (NH3 0.13 x 10-3 mol/L e PVP 0.19 g/L) implantados no tecido conjuntivo dorsal de ratos Wistar por 7, 15, 30, 60 e 90 dias. Os espécimes foram corados com hematoxilina e eosina e foram realizadas avaliações qualitativa e quantitativa. SNP inibiram a viabilidade celular no teste in vitro de maneira concentração-dependente. SNP-A foram mais tóxicas para L929 que as partículas estabilizadas com PVP. O exame histológico mostrou que SNP 540 μg/mL induziram reação tecidual significantemente mais intensa em 30 e 60 dias comparado aos grupos controles (solução fisiológica 0,9% e fibrina) nos mesmos períodos. As respostas inflamatórias causadas por SNP 1,0 μg/mL, NH3 0,13 x 10- 3 mol/L e PVP 0,19 g/L foram similares aos controles em todos os períodos experimentais. Foi possível concluir que a exposição à SNP reduziu a viabilidade de células L929 de maneira concentração-dependente. O tipo de agente estabilizante interferiu na citotoxicidade sendo SNP-A mais tóxica para L929. Ambos os tipos de soluções coloidais de nanopartículas de prata (SNP-A e SNP-P) a 540 µg/mL induziram significante resposta inflamatória no tecido subcutâneo de rato.


The aim of this study was to investigate the effect of different colloidal silver nanoparticles on cell viability of mouse fibroblasts (cell line L929) and on the subcutaneous connective tissue reaction of rats. Silver nanoparticles (SNP) of average size 5 nm were synthesized by the reduction of silver nitrate through sodium citrate and were stabilized with ammonia (SNP-A) or polyvinylpyrrolidone (SNP-P). To evaluate the cell viability, L929 cell were exposure to silver nanoparticles (0.1-100 μg/mL), and after 6, 24 and 48h MTT assay was performed. The tissue reaction was carried out with polyethylene tubes containing silver nanoparticles (1.0 μg/mL; 540 μg/mL) implanted in the dorsal connective tissue of Wistar rats for 7, 15, 30, 60, and 90 days. The specimens were stained with hematoxylin and eosin and qualitative and quantitative evaluations of the reaction were carried out. Silver nanoparticles inhibited the cell viability in the in vitro test in a concentration-dependent manner. SNP-A were more toxic to L929 than particles stabilized with polyvinylpyrrolidone (PVP). Histological examination showed that SNP at 540 μg/mL induced significant tissue reaction on 30 and 60 days after implantation compared to the controls groups (fibrin and saline 0.9%) at the same periods. The inflammatory responses caused by SNP at 1.0 μg/ml, NH3 at 0.13 x 10-3 mol/L and PVP at 0.19 g/L solutions were similar to the controls groups in all experimental periods. It was possible to conclude that SNP exposure decreased the viability of L929 cells in a concentration-dependent manner. The type of stabilizing agent interfered on the cytotoxicity of SNP being SNP-A more toxic to L929. Also, both colloidal silver nanoparticles (SNP-A and SNP-P) at 540 μg/mL induced significant inflammatory response in rat’s subcutaneous tissue.


Asunto(s)
Ensayo de Materiales , Nanopartículas del Metal , Plata , Toxicidad
11.
J Prosthodont ; 21(1): 7-15, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22050139

RESUMEN

PURPOSE: The aim of this study was to evaluate a denture base resin containing silver colloidal nanoparticles through morphological analysis to check the distribution and dispersion of these particles in the polymer and by testing the silver release in deionized water at different time periods. MATERIALS AND METHODS: A Lucitone 550 denture resin was used, and silver nanoparticles were synthesized by reduction of silver nitrate with sodium citrate. The acrylic resin was prepared in accordance with the manufacturers' instructions, and silver nanoparticle suspension was added to the acrylic resin monomer in different concentrations (0.05, 0.5, and 5 vol% silver colloidal). Controls devoid of silver nanoparticles were included. The specimens were stored in deionized water at 37°C for 7, 15, 30, 60, and 120 days, and each solution was analyzed using atomic absorption spectroscopy. RESULTS: Silver was not detected in deionized water regardless of the silver nanoparticles added to the resin and of the storage period. Micrographs showed that with lower concentrations, the distribution of silver nanoparticles was reduced, whereas their dispersion was improved in the polymer. Moreover, after 120 days of storage, nanoparticles were mainly located on the surface of the nanocomposite specimens. CONCLUSIONS: Incorporation of silver nanoparticles in the acrylic resin was evidenced. Moreover, silver was not detected by the detection limit of the atomic absorption spectrophotometer used in this study, even after 120 days of storage in deionized water. Silver nanoparticles are incorporated in the PMMA denture resin to attain an effective antimicrobial material to help control common infections involving oral mucosal tissues in complete denture wearers.


Asunto(s)
Resinas Acrílicas/química , Bases para Dentadura , Plata/análisis , Resinas Acrílicas/farmacología , Candida albicans/efectos de los fármacos , Coloides/síntesis química , Coloides/farmacología , Dentadura Completa , Ensayo de Materiales , Nanopartículas , Espectrofotometría Atómica
12.
J Endod ; 37(2): 250-4, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21238812

RESUMEN

INTRODUCTION: The aim of this study was to evaluate the rat alveolar bone response after the implantation of experimental light-cured mineral trioxide aggregate (MTA) or Angelus MTA (Angelus, Londrina, Paraná, Brazil) by histological and fluorescence analysis. METHODS: Thirty Wistar Albino rats were divided into three groups. In the control group, empty polyethylene tubes were inserted into the rat alveolar sockets immediately after extraction. In the other groups, the tubes were filled with light-cured MTA or Angelus MTA. Five animals from each group were injected with calcein on day 7, alizarin on day 14, and oxytetracycline on day 21. On day 30, these animals were killed, and the right hemimaxillas were removed and histologically processed. Half of the maxillas were processed and stained with hematoxylin and eosin. The remaining maxillas were processed for fluorescence analysis and stained with Stevenel blue and alizarin red. New bone was histomorphometrically evaluated using a Merz grid. RESULTS: The light-cured MTA presented a similar response when compared with Angelus MTA; it was characterized by a mild inflammatory response and complete bone healing. In the light-cured MTA group, the fluorescence areas were more evident at 21 days, showing an increase in bone formation. However, dystrophic mineralization was observed only with Angelus MTA. CONCLUSIONS: It was concluded that both materials present a similar inflammatory response and bone healing, but dystrophic mineralization was observed only with Angelus MTA.


Asunto(s)
Compuestos de Aluminio/farmacología , Proceso Alveolar/efectos de los fármacos , Materiales Biocompatibles/farmacología , Compuestos de Calcio/farmacología , Oseointegración/efectos de los fármacos , Óxidos/farmacología , Silicatos/farmacología , Alveolo Dental/efectos de los fármacos , Animales , Combinación de Medicamentos , Curación por Luz de Adhesivos Dentales/métodos , Masculino , Ratas , Ratas Wistar
13.
Gerodontology ; 28(2): 91-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20604810

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the overnight wearing and cleaning habits of complete denture wearers. BACKGROUND: Successful complete denture treatment can be achieved when the patients are motivated and aware of appropriate denture wear and hygiene. MATERIALS AND METHODS: A sample of 224 complete denture wearers (162 women) aged 37-89 years was studied. Inclusion criteria comprised edentulous subjects who had received their new complete dentures between 2000 and 2005 in the Dental Clinic of the Araçatuba and Araraquara Dental School, São Paulo State University. Ethical approval was sought and granted. Subjects were interviewed using questions related to overnight denture wearing and denture cleaning habits. Possible statistical relationships among some of items were analysed by the chi-square test at 5% significance level. RESULTS: Of the patients, 55.8% removed their dentures during the overnight period and 88% did this every day. Among them, 66.4% removed both dentures. Most of the patients used brushing with toothpaste (105 patients - 46.87%) as a cleaning method. More than a half of the subjects (63.4%) showed biofilm and calculus on their dentures. CONCLUSION: The patients need instructions and motivation concerning denture hygienic and denture removal overnight.


Asunto(s)
Dentadura Completa/estadística & datos numéricos , Higiene Bucal/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Biopelículas , Brasil , Cálculos Dentales/clasificación , Alisadura de la Restauración Dental , Dentadura Completa/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sueño , Encuestas y Cuestionarios , Factores de Tiempo , Cepillado Dental/estadística & datos numéricos , Pastas de Dientes/uso terapéutico
14.
J Craniofac Surg ; 21(2): 565-7, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20216436

RESUMEN

The health of a peri-implant tissue is a critical factor for the long-term success of treatment with extraoral implants. However, infection and inflammation may occur and lead to implant loss and prostheses failure. Therefore, some postsurgical care as hygiene with soap and water, soft toothbrush, and Superfloss type dental floss and medication with anti-inflammatory and antibiotic are suggested to avoid complications. In addition, a thin and smooth layer of subcutaneous tissue in the peri-implant area should be preserved during implant insertion to favor the assistance recommended in this phase.


Asunto(s)
Cuidados Posteriores , Cara/cirugía , Prótesis e Implantes , Implantación de Prótesis , Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico , Humanos , Complicaciones Posoperatorias/prevención & control , Infecciones Relacionadas con Prótesis/prevención & control , Cuidados de la Piel , Jabones/uso terapéutico , Tejido Subcutáneo/anatomía & histología , Resultado del Tratamiento
15.
Araçatuba; s.n; 2010. 114 p. ilus, tab.
Tesis en Portugués | BBO - Odontología | ID: biblio-866264

RESUMEN

O objetivo do presente estudo foi verificar a atividade antimicrobiana de uma resina acrílica à base de poli (metil metacrilato) (PMMA) contendo nanopartículas de prata frente ao microorganismo Candida albicans. Utilizou-se a resina acrílica termopolimerizável Lucitone 550 e as nanopartículas de prata foram sintetizadas por meio da redução dos íons prata do nitrato de prata pelo citrato de sódio. A forma e o tamanho das partículas foram confirmados por microscopia eletrônica de varredura (MEV) e de transmissão (MET), tendo-se obtido partículas na forma esférica e com tamanhos médios de 5 e 10 nm. A resina acrílica foi proporcionada de acordo com as instruções do fabricante e a solução coloidal de nanopartículas de prata foi adicionada ao componente líquido da resina acrílica nas concentrações de 0,05%, 0,5% e 5% baseadas na massa do polímero. Após o processamento, os espécimes foram esterilizados por radiação de Co-60. Foram analisados a adesão de microorganismos à superfície do poli (metil metacrilato)/prata (PMMA/Ag) e a formação de biofilme por Candida albicans sobre a superfície polimérica através de microscopia de luz e de MEV. Os resultados mostraram redução estatisticamente significante (P < 0,05) da adesão de microorganismos à superfície do nanocompósito para os grupos com 0,05 e 0,5% de nanopartículas de prata com tamanho de 5nm quando comparados ao grupo controle. A microscopia de luz nãomostrou diferença na formação de biofilme entre os grupos dos nanocompósitos e o grupo controle. A MEV sugeriu uma redução na quantidade de células na superfície dos grupos contendo nanopartículas de prata, especialmente até 12 horas de crescimento fúngico. Os resultados sugerem ação inibitória sobre a adesão e formação de biofilme por Candida albicans quando da adição de nanopartículas de prata de tamanho 5 nm à resina acrílica nas concentrações de 0,05% e 0,5%


The aim of this study was to verify the antimicrobial activity of a poly (methyl methacrylate) acrylic resin containing silver nanoparticles against Candida albicans microorganism. The heat-polymerized acrylic resin Lucitone 550 was used and the silver nanoparticles were synthesized through the reduction of silver ions of silver nitrate by sodium citrate. The shape and size of the particles were confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and showed spherical particles with medium size of 5 and 10 nm. The acrylic resin was proportioned according to the manufacturer’s instructions and the silver nanoparticles colloid solution was added to the liquid of the acrylic resin in 0.05%, 0.5% and 5% of concentration based on the polymer mass. After being processing, the specimens were sterilized by Co-60 radiation. The adhesion of cells of Candida albicans and the biofilm formation on the surface of the polymer were evaluated by light microscopy and SEM. The results demonstrated significantly reduction (P < .05) of the microorganisms adhesion on the surface of the nanocomposites for the groups containing 0.05 and 0.5% of silver nanoparticles with size of 5nm when compared to the control group. The light microscopy did not show difference in the biofilm formation among the groups evaluated. The SEM images suggested reduction of growth of Candida albicans cells for the nanocomposite groups, mainly up to the period of 12 hours. It was concluded that the addition of silver nanoparticles with size of 5 nm to the PMMA in 0.05% and 0.5% concentrations showed antimicrobial effect against Candida albicans


Asunto(s)
Candida albicans , Nanopartículas , Nanotecnología , Polimetil Metacrilato , Plata
16.
Int J Antimicrob Agents ; 34(2): 103-10, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19339161

RESUMEN

Research has clarified the properties required for polymers that resist bacterial colonisation for use in medical devices. The increase in antibiotic-resistant microorganisms has prompted interest in the use of silver as an antimicrobial agent. Silver-based polymers can protect the inner and outer surfaces of devices against the attachment of microorganisms. Thus, this review focuses on the mechanisms of various silver forms as antimicrobial agents against different microorganisms and biofilms as well as the dissociation of silver ions and the resulting reduction in antimicrobial efficacy for medical devices. This work suggests that the characteristics of released silver ions depend on the nature of the silver antimicrobial used and the polymer matrix. In addition, the elementary silver, silver zeolite and silver nanoparticles, used in polymers or as coatings could be used as antimicrobial biomaterials for a variety of promising applications.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Infecciones Bacterianas/prevención & control , Equipos y Suministros/microbiología , Plata/farmacología , Biopelículas/efectos de los fármacos , Humanos , Polímeros/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...